40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Fri Apr 18 20:17:17 2014, Jenne, Update, LSC, ALS noisy ALS_1kHzRMSnoise.pdfALS_oolNoise.pdf
    Reply  Mon Apr 21 22:53:16 2014, manasa, Update, LSC, ALS noise ALSX_FreeInLoop.jpgALSXY_inLoop.jpg
       Reply  Tue Apr 22 01:11:42 2014, Jenne, Update, LSC, TRY 60Hz noise TRY_60Hz_noise_21Apr2014.pdf
          Reply  Tue Apr 22 21:54:50 2014, manasa, Update, LSC, TRY 60Hz noise 60HzTRY.jpg
             Reply  Tue Apr 22 22:49:10 2014, rana, Update, LSC, TRY 60Hz noise 
                Reply  Wed Apr 23 19:58:00 2014, manasa, Update, LSC, TRY 60Hz noise 
                   Reply  Tue May 6 18:32:14 2014, steve, Update, LSC, TRY 60Hz noise hunt ETMY-ISCT_EISOL.jpg
                      Reply  Wed May 7 14:01:36 2014, steve, Update, LSC, TRY 60Hz noise hunt 
                         Reply  Thu May 8 17:25:17 2014, steve, Update, LSC, TRY 60Hz noise hunt 
                         Reply  Fri May 16 16:08:12 2014, steve, Update, LSC, Isolating base plates ISObaseplates.jpg
                Reply  Wed Apr 23 23:48:30 2014, manasa, Update, LSC, Y end whitening board IMG_1378.JPGIMG_1379.JPGIMG_1378.JPG
                   Reply  Thu Apr 24 14:23:09 2014, not manasa, Update, LSC, Y end whitening board 
                      Reply  Thu Apr 24 23:55:31 2014, Koji, Update, LSC, Y end whitening board P4245550.JPG
                         Reply  Fri Apr 25 10:43:57 2014, Koji, Update, LSC, (Fixed) Y end whitening board D990399-B_40m.pdfP4245552.JPGP4245553.JPGP4245551.JPG
                            Reply  Thu Dec 11 18:12:46 2014, ericq, Update, LSC, (Fixed) Y end whitening board 
                               Reply  Thu Dec 11 22:44:23 2014, rana, Update, LSC, QPD screens 
          Reply  Thu Apr 24 00:11:35 2014, Jenne, Update, LSC, Yend shutter back. 
       Reply  Sun Apr 27 20:26:19 2014, Koji, Update, LSC, Phase Tracker servo characterization ALSX_PTTF.pdfALSY_PTTF.pdf
          Reply  Sun Apr 27 21:30:59 2014, Koji, Update, LSC, ALS servo characterization ALSX_OLTF.pdfALSY_OLTF.pdf
             Reply  Mon Apr 28 10:24:10 2014, Koji, Update, LSC, error signal characterization ALSX_SPE.pdfALSY_SPE.pdf
                Reply  Mon Apr 28 10:34:51 2014, Koji, Update, LSC, new ALS servo design ALSX_OLTF_new2.pdfALSY_OLTF_new2.pdf
                   Reply  Mon Apr 28 10:48:48 2014, Koji, Update, LSC, new ALS servo design: comparison ALSX_OLTF_new.pdfALSY_OLTF_new.pdf
                      Reply  Mon Apr 28 10:59:54 2014, Koji, Update, LSC, New ALS servo design: expected error signals ALSX_SPE_new.pdfALSY_SPE_new.pdf
                         Reply  Mon Apr 28 11:08:11 2014, Koji, Update, LSC, New ALS servo design: expected error signals 140421_ALS_servo.zip
Message ID: 9844     Entry time: Wed Apr 23 23:48:30 2014     In reply to: 9842     Reply to this: 9849
Author: manasa 
Type: Update 
Category: LSC 
Subject: Y end whitening board 

The MON outputs of the Y end QPD whitening board were hot earlier today while pulling it out of the crate. After swapping the 4 pin lemo connector with an isolated panel mount bnc connector, I stuck the board back into the crate and this immediately kicked the ETMY suspension. Jenne and I went to the Y end to look at what was going on. We removed the board from the crate after smelling something burning. The MON output ports of the whitening board were super hot this time. There is no sign of any components melting on the board (comparing the board with its pictures that were taken earlier) and a tester board stuck into the crate lights up just fine.

So the back panel is still ok. We need to troubleshoot or replace the whitening board.

Edit, JCD:  The attached photos are from right after I replaced the "Rgain" resistor, elog 9823.  What they show is that it looks like some of the melting / burning may have already been happening before I pulled the board, and I just never noticed :(  In particular, look at the resistors on the main board above the blue "G" sticker.  There isn't a difference that I can tell between this photo from last week, and today's situation. 

 

 IMG_1378.JPG

Attachment 1: IMG_1378.JPG  498 kB  Uploaded Thu Apr 24 01:04:07 2014  | Hide | Hide all | Show all
IMG_1378.JPG
Attachment 2: IMG_1379.JPG  525 kB  Uploaded Thu Apr 24 01:04:21 2014  | Show | Hide all | Show all
ELOG V3.1.3-